diff --git a/apps/cistech-tunnel/build/Dockerfile b/apps/cistech-tunnel/build/Dockerfile
index e6e3032..4b4c6fb 100644
--- a/apps/cistech-tunnel/build/Dockerfile
+++ b/apps/cistech-tunnel/build/Dockerfile
@@ -67,17 +67,26 @@ RUN apt-get update && apt-get install -y \
     libxkbcommon0 \
     libxkbcommon-x11-0 \
     fonts-liberation \
-    # EGL/GL for PyQt6 WebEngine
+    # EGL/GL for PyQt6 WebEngine + software rendering
     libegl1 \
     libgl1 \
     libopengl0 \
-    # XCB libraries for Qt6
+    libdbus-1-3 \
+    mesa-utils \
+    libgl1-mesa-dri \
+    # XCB libraries for Qt6 (complete set)
+    libxcb1 \
     libxcb-cursor0 \
     libxcb-icccm4 \
     libxcb-image0 \
     libxcb-keysyms1 \
+    libxcb-render0 \
     libxcb-render-util0 \
+    libxcb-shm0 \
+    libxcb-xfixes0 \
     libxcb-xinerama0 \
+    libxcb-randr0 \
+    libxcb-glx0 \
     libxcb-shape0 \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
diff --git a/apps/cistech-tunnel/build/scripts/entrypoint.sh b/apps/cistech-tunnel/build/scripts/entrypoint.sh
index 33270ea..96bf7f4 100644
--- a/apps/cistech-tunnel/build/scripts/entrypoint.sh
+++ b/apps/cistech-tunnel/build/scripts/entrypoint.sh
@@ -3,8 +3,14 @@
 
 set -euo pipefail
 
+# Force software rendering (no GPU/OpenGL)
+export QT_QUICK_BACKEND=software
+export LIBGL_ALWAYS_SOFTWARE=1
+export GALLIUM_DRIVER=llvmpipe
+export MESA_GL_VERSION_OVERRIDE=3.3
+
 # Qt/Chromium flags for running as root
-export QTWEBENGINE_CHROMIUM_FLAGS="--no-sandbox --disable-gpu"
+export QTWEBENGINE_CHROMIUM_FLAGS="--no-sandbox --disable-gpu --use-gl=swiftshader"
 export QTWEBENGINE_DISABLE_SANDBOX=1
 
 # Setup TigerVNC password file from env var (passed by runtipi)
diff --git a/apps/cistech-tunnel/shared/xstartup b/apps/cistech-tunnel/shared/xstartup
index e145a3d..e94ba11 100644
--- a/apps/cistech-tunnel/shared/xstartup
+++ b/apps/cistech-tunnel/shared/xstartup
@@ -14,12 +14,18 @@ export XDG_RUNTIME_DIR=/tmp/runtime-root
 mkdir -p $XDG_RUNTIME_DIR
 chmod 700 $XDG_RUNTIME_DIR
 
+# Force software rendering (no GPU/OpenGL)
+export QT_QUICK_BACKEND=software
+export LIBGL_ALWAYS_SOFTWARE=1
+export GALLIUM_DRIVER=llvmpipe
+export MESA_GL_VERSION_OVERRIDE=3.3
+
 # GPU/WebKit workarounds for Cisco UI
 export GDK_BACKEND=x11
 export WEBKIT_DISABLE_DMABUF_RENDERER=1
 
 # Qt/Chromium flags for running as root (no sandbox)
-export QTWEBENGINE_CHROMIUM_FLAGS="--no-sandbox --disable-gpu"
+export QTWEBENGINE_CHROMIUM_FLAGS="--no-sandbox --disable-gpu --use-gl=swiftshader"
 export QTWEBENGINE_DISABLE_SANDBOX=1
 
 # Start dbus session